[The ability of frequency doubling technology to detect abnormality of visual function in early glaucoma].

PURPOSE: To evaluate the ability of the Frequency Doubling Technology(FDT) threshold test in detecting abnormality of visual function in early glaucoma patients.

SUBJECTS AND METHOD: The C-20 full threshold test of FDT was performed on 34 normal-tension glaucoma(NTG) patients and 39 primary open-angle glaucoma(POAG) patients with visual field defects limited to the upper or lower hemi-field as detected by Humphrey Field Analyzer(HFA) and on 79 normal control subjects. Optic disk findings and FDT results corresponding to the intact hemi-field were evaluated. FDT abnormalities in normal subjects were calculated as false positive rates in FDT.

RESULT: The sensitivity and specificity of FDT, calculated based on optic disk findings, were 75.0% and 61.1% in POAG, and 61.1% and 66.7% in NTG, respectively, while the false positive rate in normal subjects was 11.4%.

CONCLUSION

FDT can detect glaucomatous functional abnormality earlier than HFA.